Methane Collection Systemīacteria break down the trash in the absence of oxygen (anaerobic) because the landfill is airtight. These pipes then drain into a leachate pipe, which carries leachate to a leachate collection pond. To collect leachate, perforated pipes run throughout the landfill. This water with contaminants is called leachate and is typically acidic. As the water trickles through the trash, it picks up contaminants. The water percolates through the cells and soil in the landfill similar to how water percolates through ground coffee in a drip coffee maker. No system to exclude water from the landfill is perfect and water does get into the landfill. Once settling has occurred and the water has passed tests, it is then pumped or allowed to flow off-site. In the collection ponds, suspended soil particles are allowed to settle and the water is tested for leachate chemicals. The ditches are either concrete or gravel-lined and carry water to collection ponds to the side of the landfill. Plastic drainage pipes and storm liners collect water from areas of the landfill and channel it to drainage ditches surrounding the landfill's base. Concrete, plastic or metal culverts underneath nearby roads and stormwater basins, which can reduce the suspended sediment in the water to minimize soil loss from the landfill, are other parts of the system. To keep rainwater out, a landfill has a storm drainage system to route the runoff into drainage ditches and away from the buried trash. Once the cell is made, it is covered with 6 inches (15 centimeters) of soil and compacted further. Trash is compacted by heavy equipment into areas, called cells, which typically contain a day's worth of refuse to get the most use of the volume of space in the landfill. The bottom liner, made of thick plastic, prevents the trash from coming in contact with the outside soil, particularly the groundwater. Bottom Liner SystemĪ landfill's major purpose and one of its biggest challenges is to contain the trash so that the trash doesn't cause problems in the environment. So, as we discuss each part of the landfill, we'll explain what problem is solved. In the sections that follow, we'll go into more detail about how landfills are designed and built, and how they work. That layer of soil helps reduce the odor and problems with insects and rodents, and also prevents trash from getting out of the landfill and turning into litter. Landfills also must use federally approved operating practices for handling the trash, which include compacting and covering it frequently with several inches of soil. They have a composite liner on top of 2 feet (0.61 meters) of compacted clay soil on the bottom and sides, as well as systems to capture leachate, the water that percolates down through the trash, before it can contaminate groundwater.Īdditionally, landfills are equipped with groundwater testing wells to make sure that pollution isn't escaping.

In addition, municipal solid waste landfills also are allowed to take some other types of nonhazardous waste from businesses and industry. These facilities, which are designed and operated to conform to federal regulations, primarily are for the purpose of handling household trash. Today, there are about 2,600 landfills that handle municipal solid waste across the U.S. In 1976, Congress passed the Resource Conservation and Recovery Act, which imposed requirements on landfills to prevent them from polluting the environment. Instead of just dumping or burning trash, it was systematically buried, compacted with heavy equipment, and then covered. Modern sanitary landfills - the first of which was created in California back in 1937 - became the solution to this problem.

Additionally, the USPHS found that open-burning dumps were causing respiratory harm and posed disease threats, and polluted groundwater as well.

Public Health Service (USPHS) issued a disturbing report, in which it predicted that solid waste generation would double in 20 years' time, and that urban areas would run out of nearby land for garbage disposal.

Into the trash it goes money